1. Field of the Invention
The present invention relates to an image processing apparatus requiring user authentication for use of the apparatus or a function thereof, and a user authentication method for the image processing apparatus.
2. Description of the Related Art
There is known an image processing apparatus allowing an authenticated user to use the apparatus, and application software for realizing user authentication in an image processing apparatus. Hereinafter, the term “device authentication” is used to refer to user authentication performed for allowing or limiting use of an apparatus
Some of apparatuses employing the device authentication are configured to measure a time period that a user does not apply any operation while being logging in after user authentication, and automatically cause the user to logout if the user does not operate the apparatus for a predetermined time, for example, as discussed in Japanese Patent Application Laid-Open No. 2007-249417. Hereinafter, the term “auto-logout” is used to refer to this function.
According to Japanese Patent Application Laid-Open No. 2007-249417, the time period for the auto-logout can be changed for each user. Further, the time period for the auto-logout can be varied according to the degree of difficulty of an operation menu.
On the other hand, there is known an image processing apparatus allowing an authenticated user to use a specific function such as the send function or the print function. Hereinafter, the term “function authentication” is used to refer to user authentication performed for allowing or limiting use of a specific function provided to an apparatus.
Some image processing apparatuses are equipped with authentication means of both the device authentication and the function authentication, or equipped with a plurality of kinds of the function authentication. In this case, a user performs an operation for the device authentication enabling the user to use the image processing apparatus, and after that, performs an operation for the function authentication to use a specific function. Conventionally, this kind of apparatus is equipped with, for example, a logout button dedicated to each authentication on a touch panel, a keyboard, or the like.
However, conventional apparatuses using a plurality of kinds of authentication require a user to log out from both of the device authentication and the function authentication after the user is allowed to log in through an operation for the device authentication and an operation for the function authentication, and uses the image processing apparatus.
However, for example, a user, who actually intends to log out from the device authentication, may mistakenly log out from the function authentication and leaves the apparatus without being aware of his/her mistake. In this case, while the apparatus is left in such a state that this user is logging in the device authentication, another user may use the apparatus. This situation may lead to execution of a job by using a false identity.